Residuals in drinking water as a consequence of hypochlorite disinfection

Cilj ovog rada je odrediti nusprodukte u vodi za piće kao posljedica dezinfekcije natrijevim hipokloritom (NaOCl). Nusprodukti dezinfekcije u vodi za piće imaju negativan učinak na zdravlje čovjeka. Nusprodukti su analizirani ionskom i plinskom kromatografijom. Analiza je pokazala da su kao nusprodukti dezinfekcije NaOCl-om u vodi za piće prisutni klorati i trihalometani, dok prisutnost klorita, bromida i bromata nije dokazana. Koncentracije klorata i trihalometana u vodi za piće su ispod maksimalno dopuštene koncentracije (MDKClO3-=400,0 μg/L, MDKTHMuk=100 μg/L). Određene su i koncentracije ukupnog organskog ugljika (TOC) koje se kreću od 1,6 mg/L do 4,0 mg/L i utrošak kalijevog permanganata (KMnO4) koji je manji od 5,0 mg/L (MDK). Na temelju tih rezultata može se zaključiti da voda za piće ne sadrži preveliku količinu organskih tvari koje služe kao prekursori za nastajanje nusprodukata dezinfekcije.The aim of this study was to determine the residuals in drinking water as a consequence of hypochlorite disinfection. Disinfection residuals in drinking water have a negative influence on human health. Residuals were analyzed by ion and gas chromatography. Analysis showed that drinking water contain chlorates and trihalomethanes as residuals of hypochlorite disinfection, while the presence of chlorite, bromide and bromate has not been proven. The concentrations of chlorates and trihalomethanes in drinking water are below the maximum allowable concentration. Maximum allowable concentration of chlorates is 400,0 μg/L, and the maximum allowable concentration of trihalomethanes is 100 mg/L. Also, the concentrations of total organic carbon (TOC) were determined, and ranges from 1.6 mg/L to 4.0 mg/L and consumption of KMnO4 is less than 5.0 mg/L. Based on these results we can conclude that concentration of organic matter in drinking water is low, which are precursor for the formation of disinfection residuals